Dr. Sarah Berry is a Harvard Medical School trained Geriatrician and Instructor in Medicine at Hebrew Rehabilitation Center. Dr. Berry's long term objective is to become an academic geriatrician and independent investigator with expertise in the epidemiology and outcomes of falls and fractures. Her previous work has focused largely on the epidemiology of second fractures in elderly persons. It is important that future efforts to prevent fractures focus not only on bone strength, but on fall prevention as well. Medication use is a common and potentially modifiable risk factor for falls in the nursing home setting. Therefore, the primary objectives of her learning curriculum are to increase her knowledge of fall prevention and pharmacoepidemiology, and to improve her skills in study design methodology. The aims of this research project are to describe the frequency of medication changes in the nursing home population, and to determine the effects of medication changes on the acute risk of falls using a unique and appropriate study design: the case-crossover study. The applicant will also assess whether the effects of a particular medication change on the acute risk of falls is greater among ambulatory residents compared with non-ambulatory residents, and among residents with high baseline medication use compared to residents with low baseline medication use. The estimate of the effect of medication changes on the risk of falls will be determined by comparing the frequency of medication changes during the time period just prior to the fall, and comparing this with the frequency of medication changes during non-fall periods in the same individual. This Mentored Patient-Oriented Career Development Award will provide the necessary additional training to develop into an independent investigator in the field of aging, and the proposed project will produce several manuscripts and preliminary data for the applicant to write and submit an R01 application by the final year of the award.